Method for prolonging shelf life of prepared vegetable by combining cinnamon essential oil microcapsules and high-voltage electrostatic field

Abstract

The invention discloses a method for prolonging the shelf life of premade dishes by combining cinnamon essential oil microcapsules and a high-voltage electrostatic field. The preparation method comprises the following main steps: preparing a purple perilla protein isolate-octenyl succinic acid starch compound; preparing a cinnamon essential oil nano-emulsion; and freeze-drying to obtain the cinnamon essential oil microcapsule. And then adding the mixture into the pre-prepared dish. Then, the prepared dish is put into a high-voltage electrostatic field to be treated. The prepared cinnamon essential oil microcapsule is high in heat resistance, the embedding rate of the cinnamon essential oil can reach 84.81 + / -0.11%, and the loading rate reaches 53.67 + / -2.5%; the total number of bacterial colonies of the prepared vegetable prepared by adding the cinnamon essential oil microcapsules is remarkably reduced during storage, and the shelf life of the prepared vegetable can be effectively prolonged. And after the high-voltage electrostatic field is combined, the shelf life of the prefabricated vegetables is further prolonged. The method provided by the invention is simple in preparation, meets the expectation of the public on the preservative-free prefabricated dish, and has a wide application prospect.

Description

Technical Field

[0001] The present invention discloses a method for extending the shelf life of prefabricated dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic field, belonging to the field of food processing technology. Background Art

[0002] Spice essential oils are highly concentrated flavor and active substances extracted from natural spices. They have strong aroma, flavor and coloring functions, and at the same time exhibit excellent antibacterial and antioxidant activities. They have wide applications and great market potential in the food flavoring and preservation industries. Applying essential oils in food can help optimize the freshness of food, extend its shelf life, and reduce food spoilage and losses. Using appropriate spice essential oils as natural preservatives to replace traditional chemical preservatives can produce healthier and safer prefabricated dish products.

[0003] At the same time, high-voltage electrostatic field sterilization and preservation is a new preservation method. It is a non-thermal sterilization method that will not cause loss of nutrients due to high temperature. The high-voltage electrostatic field sterilization technology can effectively improve the safety, nutritional value, flavor retention and shelf life of prefabricated dishes, reduce the use of chemical additives, meet the preferences of modern consumers for healthy and natural foods, and is conducive to enhancing the market competitiveness of products.

[0004] The present invention applies cinnamon essential oil to prefabricated dishes and observes its preservation and antioxidant effects during the preparation process. However, due to the strong flavor of cinnamon essential oil, attention should be paid to its impact on the flavor of the prepared dishes during application. To reduce the strong impact of cinnamon essential oil on the flavor, it is encapsulated with a complex coacervation microcapsule using perilla seed protein - octenyl succinic anhydride starch sodium as the wall material, and the microcapsule is formed by freeze-drying and added to the prefabricated dishes. At the same time, in order to further extend the shelf life, high-voltage electrostatic field treatment is also used.

[0005] Patent CN114831267A discloses a natural deodorizing and flavor-enhancing microcapsule-type essence and its preparation method. The microcapsule prepared in this invention uses a complex spice essential oil as the core material and octenyl succinic anhydride starch sodium and maltodextrin as multi-layer wall materials to encapsulate the essence essential oil. The prepared microcapsule-type essence can reduce the fishy smell in meat product processing. Different from it, the perilla seed protein - octenyl succinic anhydride starch sodium microcapsule prepared in the present invention can well shield the pungent smell of the essential oil itself.

[0006] Patent CN112869050B discloses a preparation method of prickly ash essential oil microcapsules and their application in fried foods. The microcapsules prepared by this invention use prickly ash essential oil as the core material, sodium octenyl succinate starch and maltodextrin as the multi-layer wall materials, and are formed by emulsion embedding and spray drying. The suitable addition amount of the prepared prickly ash essential oil microcapsules in fried foods is 1.0 - 2.0%, and under high-temperature frying, the prickly ash aroma is retained, and the numbing substances are released slowly, playing a role in preventing the loss of essential oil flavor substances. This invention uses freeze-drying as the drying method, and dries under low-temperature conditions, which can more effectively retain the flavor substances of the essential oil.

[0007] Patent CN115997909A discloses a microcapsule with high fluidity and its preparation method. The microcapsules prepared by this invention use perilla protein isolate and perilla polysaccharide as the first-layer wall materials, trehalose and silica as the second-layer wall materials, and spice essential oil as the core material, and are dried by spray drying. Microcapsules with high fluidity are obtained. The preparation process of this multi-layer embedded microcapsule is complex, while the microcapsules prepared by this invention are simple to prepare, only requiring one-layer embedding, and are suitable for large-scale production and preparation.

[0008] Patent CN118575854A discloses a preservation method for fish meat. This invention uses wine pomace polyphenol-chitosan composite film solution to coat and high-voltage electrostatic field to treat fish meat, and places the treated fish meat at 4°C for preservation. Patent CN118415219A discloses a preservation method for sturgeon caviar based on high-voltage electrostatic field. This invention directly stores sturgeon caviar in a high-voltage electrostatic field, effectively delaying the quality deterioration of sturgeon caviar, and is applicable to the long-term preservation of sturgeon caviar. These methods do not involve the application of using spice essential oil microcapsules combined with high-voltage electrostatic field for preservation in prefabricated dishes. Summary of the Invention

[0009] The cinnamon essential oil microcapsules of this invention can effectively encapsulate cinnamon essential oil through the coating layer formed by perilla protein isolate-sodium octenyl succinate starch, reduce the volatilization of cinnamon essential oil, and can be well applied to prefabricated dishes under high-temperature conditions. The microcapsules of this invention have good high-temperature resistance while maintaining the anti-corrosion characteristics of cinnamon essential oil. And there is no publicly disclosed cinnamon essential oil microcapsule that can be applied to foods such as prefabricated dishes. High-voltage electrostatic field is a new sterilization method that can well control the loss of nutritional components, and there is no publicly disclosed application of using essential oil combined with high-voltage electrostatic field for sterilization of prefabricated dishes. Through the combination of this microcapsule and high-voltage electrostatic field, the shelf life of prefabricated dishes can be extended without adding preservatives.

[0010] The technical solution of this invention is as follows:

[0011] A method for extending the shelf life of prefabricated dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic field, comprising the following steps:

[0012] (1) Preparation of perilla protein isolate - octenyl succinic anhydride starch mixed solution: Disperse perilla protein isolate and octenyl succinic anhydride starch into ultrapure water respectively, and stir until completely dissolved to obtain octenyl succinic anhydride starch solution and perilla protein isolate solution respectively; Add the octenyl succinic anhydride starch solution to the perilla protein isolate solution under stirring conditions to obtain a perilla protein isolate - octenyl succinic anhydride starch mixed solution;

[0013] (2) Preparation of perilla protein isolate - octenyl succinic anhydride starch - cinnamon essential oil composite solution: Continuously stir the perilla protein isolate - octenyl succinic anhydride starch mixed solution, add cinnamon essential oil to the obtained perilla protein isolate - octenyl succinic anhydride starch mixed solution and perform high - speed shearing to obtain a perilla protein isolate - octenyl succinic anhydride starch - cinnamon essential oil composite solution;

[0014] (3) Homogenization treatment: Subject the perilla protein isolate - octenyl succinic anhydride starch - cinnamon essential oil composite solution prepared in step (2) to high - pressure homogenization to form an emulsion;

[0015] (4) Freeze - dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules;

[0016] (5) Add the prepared cinnamon essential oil microcapsules in step (4) to pre - prepared dishes;

[0017] (6) Further process the pre - prepared dishes added with cinnamon essential oil in step (5) in a high - voltage electrostatic field.

[0018] Further, in the perilla protein isolate - octenyl succinic anhydride starch mixed solution in step (1), perilla protein isolate and octenyl succinic anhydride starch are stirred in ultrapure water for 10 - 12 h respectively.

[0019] Further, in step (1), the mass concentration of the perilla protein isolate solution and the octenyl succinic anhydride starch solution is 1 - 3%.

[0020] Further, in the perilla protein isolate - octenyl succinic anhydride starch mixed solution in step (1), the mass concentration ratio of perilla protein isolate to octenyl succinic anhydride starch is 4:1 - 6:1.

[0021] Further, in step (2), the temperature of continuous stirring of the perilla protein isolate - octenyl succinic anhydride starch composite solution is 20 - 25 °C, the rotation speed is 600 - 1000 rpm, and the time is 10 - 12 h. The perilla protein isolate - octenyl succinic anhydride starch - cinnamon essential oil composite solution is sheared at 8000 - 10000 rpm by a high - speed shearing machine for 4 - 8 minutes.

[0022] Further, in step (2), the added mass of cinnamon essential oil is 0.8 to 1.2 times the mass of the perilla seed protein - octenyl succinic anhydride starch sodium complex.

[0023] Further, in step (3), the high - pressure homogenization pressure of the perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil composite solution is 30 - 40 MPa, and the number of cycles is 2 - 4 times.

[0024] Further, in step (4), the temperature of freeze - drying is - 40 to - 50 °C, and the time of freeze - drying is 13 - 15 h.

[0025] Further, in step (5), the addition amount of cinnamon essential oil microcapsules is 0.2 - 0.4% of the total mass of the pre - prepared dishes.

[0026] Further, in step (6), the voltage intensity of the high - voltage electrostatic field is 30 - 40 kV, and the treatment time is 25 - 35 minutes.

[0027] Advantages of the present invention:

[0028] (1) The present invention uses perilla seed protein and octenyl succinic anhydride starch sodium as wall materials and cinnamon essential oil as core material for embedding, and forms microcapsules through complex coacervation. By embedding cinnamon essential oil with the wall material, the pungent smell of cinnamon essential oil can be significantly reduced. Octenyl succinic anhydride starch sodium itself has good emulsifying effect, and when combined with perilla seed protein, it has a high embedding rate. At the same time, perilla seed protein has high nutritional value, which can supplement human protein, enhance physical fitness, maintain bone health and reduce cholesterol; octenyl succinic anhydride starch sodium is an efficient food emulsifier, which has the function of inhibiting bacterial growth, can keep the freshness of food, increase the stability of particles, and improve the taste and color of food. As a non - thermal sterilization technology, the high - voltage electrostatic field can minimize the loss of nutrients in pre - prepared dishes and extend the shelf life of food at the same time.

[0029] (2) The wall material used in the present invention has good thermal stability in high - temperature environments, can not be decomposed under the condition of 230 °C, can well reduce the volatilization of cinnamon essential oil, and ensure stability during the reheating process of the dishes.

[0030] (3) The present invention uses perilla seed protein and octenyl succinic anhydride starch sodium as wall materials, embeds cinnamon essential oil by complex coacervation, has a simple preparation process, wide sources of raw materials, can enhance the nutritional value when added to pre - prepared dishes, and is suitable for large - scale production.

[0031] (4) The high - voltage electrostatic field used in the present invention has simple operation, and the equipment is suitable for large - scale industrial production, and can be well applied to the preservation of pre - prepared dishes. Description of the Drawings

[0032] Figure 1 It is the inverted fluorescence image of cinnamon essential oil microcapsules;

[0033] Figure 2 They are the infrared spectra of perilla protein isolate (PPI), sodium octenyl succinate starch (OSA), cinnamon essential oil (CEO), perilla protein isolate - sodium octenyl succinate starch (PPI - OSA), and cinnamon essential oil microcapsules (CEO microcapsules);

[0034] Figure 3 They are the graphs of the total number of colonies and pH changes of pre - prepared dishes added with cinnamon essential oil microcapsules, cinnamon essential oil microcapsules combined with high - voltage electrostatic field, and those without added essential oil. Detailed implementation manners

[0035] In order to make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] Comparative example 1

[0037] A method for preparing a pre - prepared Kung Pao Chicken dish, the steps are as follows:

[0038] (1) Prepare the raw materials for the pre - prepared Kung Pao Chicken dish;

[0039] (2) Cut 500 g of chicken breast into cubes with an edge length of 2.5 cm. Put the cut chicken into a basin, add 3 g of salt, 1 g of monosodium glutamate, 1 g of pepper powder, and gradually add 2 liang of scallion and ginger water in 3 times and stir until sticky. Then add 15 g of starch and stir again, and finally stir with sealed oil;

[0040] (3) Prepare the bowl sauce: Put 20 g of soy sauce, 30 g of caster sugar, 20 g of rice vinegar, 1 g of dark soy sauce, 1 g of monosodium glutamate, 2 g of Huadiao wine, and 10 g of water - starch into a bowl and stir well;

[0041] (4) Add base oil to the pan, add Chinese prickly ash and dried chili peppers and fry until fragrant, then remove them; add the chicken and stir - fry until colored, then add scallions, ginger, and garlic and stir - fry. After that, pour in the bowl sauce, add peanuts, cucumber, and dried chili peppers, and stir - fry and then take out of the pan.

[0042] (5) Put the pre - prepared Kung Pao Chicken dish into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0043] Comparative example 2

[0044] A method for preparing a pre - prepared Yu - Xiang shredded pork dish, the steps are as follows

[0045] (1) Prepare the raw materials for the Yu - Xiang shredded pork dish;

[0046] (2) Pour 25 grams of sugar, 4 grams of salt, 2 grams of monosodium glutamate, 1 gram of pepper powder, 7 - 8 grams of soy sauce, 25 grams of rice vinegar, 10 grams of yellow rice wine, and 15 grams of water starch into a bowl and stir well;

[0047] (3) Add 2 grams of salt, 2 grams of monosodium glutamate, scallions, ginger, and cooking wine to the shredded meat, add an appropriate amount of dry corn starch and stir well, then add an appropriate amount of cooking oil and stir well;

[0048] (4) Pour oil into the pot. When the oil temperature reaches 60% heat, add the shredded meat and stir - fry until it is dispersed. Then pour out the excess oil, add minced ginger and garlic and stir - fry evenly. Put in the agaric, shredded winter bamboo shoots, and shredded carrots and stir - fry evenly. Pour in the sauce and stir - fry evenly. Finally, add chopped green onions and bright oil and stir - fry evenly, then it can be taken out of the pot and served on a plate.

[0049] (5) Put the pre - prepared fish - flavored shredded pork into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0050] Comparative Example 3

[0051] A preparation method of pre - prepared braised beef dishes is as follows:

[0052] (1) Prepare the raw materials for pre - prepared braised beef dishes;

[0053] (2) After cleaning the beef, cut it into large pieces, avoiding being too small. Put the beef into a pot, add enough cold water, heat it with high heat, skim the foam after boiling, cook for 10 minutes, then take out the beef and drain the water for later use;

[0054] (3) Take a large pot, add an appropriate amount of water, put the beef pieces into the pot. Add ginger slices, scallions, star anises, cinnamon twigs, and cooking wine. Then add light soy sauce, dark soy sauce, and white sugar to adjust the taste;

[0055] (4) Simmer the beef over medium - low heat. The simmering time is about 2 hours until the beef becomes tender and flavorful. During this period, add an appropriate amount of water in a timely manner to keep the water level in the pot so that it submerges the beef.

[0056] (5) During the simmering process, add an appropriate amount of salt according to the taste to adjust the saltiness.

[0057] (6) When the beef is simmered until it is tender and flavorful, turn the heat to low and continue to simmer until the sauce thickens slightly. Take out the beef and slice it.

[0058] (7) Put the pre - prepared braised beef dishes into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0059] Comparative Example 4

[0060] A preparation method of pre - prepared Kung Pao chicken dishes combined with cinnamon essential oil microcapsules is as follows:

[0061] (1) Prepare a mixed solution of perilla protein isolate - sodium octenyl succinate starch: Disperse perilla protein isolate and sodium octenyl succinate starch into ultrapure water respectively, and stir for 12 h until completely dissolved to obtain a sodium octenyl succinate starch solution and a perilla protein isolate solution respectively, where the mass concentration of both perilla protein isolate and sodium octenyl succinate starch is 1%; Add 1 part of the sodium octenyl succinate starch solution to 6 parts of the perilla protein isolate solution under stirring conditions to obtain a mixed solution of perilla protein isolate - sodium octenyl succinate starch;

[0062] (2) Prepare a composite solution of perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil: Continuously stir the composite solution of perilla protein isolate - sodium octenyl succinate starch at 20 - 25 °C at a speed of 600 rpm for 10 h, add cinnamon essential oil with the same solute weight as the obtained mixed solution and shear at high speed (9000 rpm) for 5 minutes to obtain a composite solution of perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil;

[0063] (3) Homogenization treatment: Homogenize the perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil prepared in step (2) under high pressure to form an emulsion; The high - pressure homogenization pressure is 35 MPa, and the cycle is 4 times;

[0064] (4) Freeze - dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; The freeze - drying temperature is - 40 °C, and the freeze - drying time is 14 h;

[0065] (5) Cut 500 g of chicken breast into cubes with a side length of 2.5 cm. Put the cut chicken into a basin, add 3 g of salt, 1 g of monosodium glutamate, 1 g of pepper, and gradually add 2 liang of scallion and ginger water in 3 portions and stir until sticky, then add 15 g of starch and stir again, and finally stir with sealed oil; (6) Bowl juice: Put 20 g of soy sauce, 30 g of caster sugar, 20 g of balsamic vinegar, 1 g of dark soy sauce, 1 g of monosodium glutamate, 2 g of Huadiao wine, and 10 g of water starch, and stir evenly;

[0066] (7) Add base oil to the pan, add Chinese prickly ash and dried chili peppers, fry until fragrant and then remove; Add the chicken and stir - fry until colored, then add scallions, ginger, and garlic and stir - fry, then pour in the bowl juice, add peanuts, cucumber, dried chili peppers, and cinnamon essential oil microcapsules with a total mass of 0.3% of the total mass of the dish, and stir - fry and then remove from the pan.

[0067] (8) Pack the pre - prepared Kung Pao Chicken dish combined with cinnamon essential oil microcapsules into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0068] Control group 5

[0069] A preparation method of a pre - prepared Yu - Xiang shredded pork dish combined with cinnamon essential oil microcapsules is as follows:

[0070] (1) Prepare a mixed solution of perilla seed protein - sodium octenyl succinate starch: Disperse perilla seed protein and sodium octenyl succinate starch into ultrapure water respectively, stir for 12 h until completely dissolved to obtain a sodium octenyl succinate starch solution and a perilla seed protein solution respectively, where the mass concentration of both perilla seed protein and sodium octenyl succinate starch is 1%; Add 1 part of the sodium octenyl succinate starch solution to 6 parts of the perilla seed protein solution under stirring to obtain a perilla seed protein - sodium octenyl succinate starch mixed solution;

[0071] (2) Prepare a composite solution of perilla seed protein - sodium octenyl succinate starch - cinnamon essential oil: Continuously stir the perilla seed protein - sodium octenyl succinate starch composite solution at 20 - 25 °C at a speed of 600 rpm for 10 h, add cinnamon essential oil with the same solute weight as the obtained mixed solution and shear at high speed (9000 rpm) for 5 minutes to obtain a perilla seed protein - sodium octenyl succinate starch - cinnamon essential oil composite solution;

[0072] (3) Homogenization treatment: Homogenize the perilla seed protein - sodium octenyl succinate starch - cinnamon essential oil prepared in step (2) under high pressure to form an emulsion; The high - pressure homogenization pressure is 35 MPa and the cycle is 4 times;

[0073] (4) Freeze - dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; The temperature of freeze - drying is - 40 °C and the time of freeze - drying is 14 h;

[0074] (5) Pour 25 g of sugar, 4 g of salt, 2 g of monosodium glutamate, 1 g of pepper, 7 - 8 g of soy sauce, 25 g of rice vinegar, 10 g of yellow rice wine, and 15 g of starch into a bowl and stir evenly;

[0075] (6) Add 2 g of salt, 2 g of monosodium glutamate, scallions - ginger - cooking wine to the shredded meat, stir evenly with an appropriate amount of dry corn starch, and then stir evenly with an appropriate amount of edible oil;

[0076] (7) Pour oil into the pan, when the oil temperature reaches 60% heat, put the shredded meat into the pan and stir - fry until it is loose, then pour out the excess oil, add ginger and garlic minced and stir - fry evenly, put in agaric, bamboo shoot shreds, and carrot shreds and stir - fry evenly, pour in the sauce and stir - fry evenly, finally put in chopped scallions, bright oil and 0.3% of cinnamon essential oil based on the total mass of the dish and stir - fry evenly, then take it out of the pan and plate;

[0077] (8) Pack the pre - prepared fish - flavored shredded pork with cinnamon essential oil microcapsules into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0078] Control Example 6

[0079] A preparation method of a pre - prepared dish of marinated beef with cinnamon essential oil microcapsules, the steps are as follows:

[0080] (1) Prepare a mixed solution of perilla protein isolate - sodium octenyl succinate starch: Disperse perilla protein isolate and sodium octenyl succinate starch into ultrapure water respectively, stir for 12 h until completely dissolved to obtain sodium octenyl succinate starch solution and perilla protein isolate solution respectively, where the mass concentration of both perilla protein isolate and sodium octenyl succinate starch is 1%; Add 1 part of sodium octenyl succinate starch solution to 6 parts of perilla protein isolate solution under stirring conditions to obtain a mixed solution of perilla protein isolate - sodium octenyl succinate starch;

[0081] (2) Prepare a composite solution of perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil: Continuously stir the composite solution of perilla protein isolate - sodium octenyl succinate starch at 20 - 25 °C at a speed of 600 rpm for more than 10 h, add cinnamon essential oil with the same solute weight as the obtained mixed solution and shear at high speed (9000 rpm) for 5 minutes to obtain a composite solution of perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil;

[0082] (3) Homogenization treatment: Homogenize the perilla protein isolate - sodium octenyl succinate starch - cinnamon essential oil prepared in step (2) under high pressure to form an emulsion; The high - pressure homogenization pressure is 35 MPa and the cycle is 4 times; (4) Freeze - dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; The freeze - drying temperature is - 40 °C and the freeze - drying time is 14 h;

[0083] (5) After cleaning the beef, cut it into large pieces, avoiding being too small. Put the beef into a pot, add enough cold water, heat it with high heat, skim the floating foam after boiling, cook for 10 minutes, and then take out the beef and drain the water for standby;

[0084] (6) Take a large pot, add an appropriate amount of water, and put the beef pieces into the pot. Add ginger slices, scallions, star anise, cinnamon leaves, and cooking wine. Then add light soy sauce, dark soy sauce, and white sugar to adjust the taste;

[0085] (7) Stew the beef over medium - low heat. The stewing time is about 2 hours until the beef becomes soft and flavorful. During this period, add an appropriate amount of water in a timely manner to keep the water level in the pot so that the beef is submerged.

[0086] (8) During the stewing process, add an appropriate amount of salt according to taste to adjust the saltiness;

[0087] (9) When the beef is stewed until soft and flavorful, turn the heat to low and continue stewing until the soup thickens slightly. Take out the beef, slice it, and add 0.3% of the total mass of cinnamon essential oil and stir evenly.

[0088] (10) Pack the prepared dish of marinated beef combined with cinnamon essential oil microcapsules into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0089] The pre-made dishes of Kung Pao Chicken, Yuxiang Shredded Pork, and Marinated Beef prepared through standardized operations in Comparative Examples 1-6 have obvious advantages in terms of convenience and taste consistency, and the flavors of the dishes are precisely controlled by standardizing the addition amounts of various ingredients. In Comparative Examples 1-3, without the addition of essential oils, there are situations where the shelf life is short, it is prone to spoilage, resulting in the loss of nutrients and even inedibility ( Figure 3 ). By adding cinnamon essential oil microcapsules, the shelf life of the pre-made dishes can be significantly extended, and the increase in the total number of colonies and pH during storage can be reduced ( Figure 3 ).

[0090] Example 1

[0091] A method for extending the shelf life of pre-made Kung Pao Chicken dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields, the steps are as follows:

[0092] (1) Prepare a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium; disperse perilla seed protein and octenyl succinic anhydride starch sodium into ultrapure water respectively, stir for 12 h until completely dissolved to obtain octenyl succinic anhydride starch sodium solution and perilla seed protein solution respectively, where the mass concentrations of perilla seed protein and octenyl succinic anhydride starch sodium are both 1%; add 1 part of octenyl succinic anhydride starch sodium solution to 6 parts of perilla seed protein solution under stirring conditions to obtain a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium;

[0093] (2) Prepare a composite solution of perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil: continuously stir the composite solution of perilla seed protein - octenyl succinic anhydride starch sodium at 20 - 25 °C at a speed of 600 rpm for 10 h, add cinnamon essential oil with the same solute weight to the obtained mixed solution and shear at high speed (9000 rpm) for 5 minutes to obtain a composite solution of perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil;

[0094] (3) Homogenization treatment: homogenize the perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil prepared in step (2) under high pressure to form an emulsion; the high-pressure homogenization pressure is 35 MPa, and the cycle is 4 times;

[0095] (4) Freeze-dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; the freeze-drying temperature is -40 °C, and the freeze-drying time is 14 h;

[0096] (5) Cut 500 g of chicken breast into cubes with a side length of 2.5 cm, put the cut chicken into a basin, add 3 g of salt, 1 g of monosodium glutamate, 1 g of pepper powder, and gradually add 2 liang of scallions and ginger water in 3 portions and stir until sticky, add 15 g of starch and stir again, then add oil and stir;

[0097] (6) Bowl sauce: Put 20 g of soy sauce, 30 g of caster sugar, 20 g of rice vinegar, 1 g of dark soy sauce, 1 g of monosodium glutamate, 2 g of huadiao wine, and 10 g of water starch, and stir well;

[0098] (7) Add a little oil to the pot, add Chinese prickly ash and dried chili peppers and fry until fragrant, then remove; add chicken and stir-fry until colored, then add scallions, ginger and garlic and stir-fry, then pour in the bowl sauce, add peanuts, cucumber, dried chili peppers and cinnamon essential oil microcapsules with a total mass of 0.3% of the total mass of the dish, and stir-fry and serve;

[0099] (8) Put the prefabricated Kung Pao Chicken dish combined with cinnamon essential oil microcapsules into a vacuum cooking bag and package it with a vacuum packaging machine;

[0100] (9) After serving, put the packaged prefabricated Kung Pao Chicken dish into a high-voltage electrostatic field and treat it with a high-voltage electrostatic field with a strength of 30 kV for 30 minutes.

[0101] Example 2

[0102] A method for extending the shelf life of a prefabricated Yuxiang shredded pork dish combined with cinnamon essential oil microcapsules and a high-voltage electrostatic field, the steps are as follows:

[0103] (1) Prepare a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium; disperse perilla seed protein and octenyl succinic anhydride starch sodium into ultrapure water respectively, stir for 12 h until completely dissolved, and obtain octenyl succinic anhydride starch sodium solution and perilla seed protein solution respectively, where the mass concentration of perilla seed protein and octenyl succinic anhydride starch sodium is 1%; add 1 part of octenyl succinic anhydride starch sodium solution to 6 parts of perilla seed protein solution under stirring conditions to obtain a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium;

[0104] (2) Prepare a perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil composite solution: continuously stir the perilla seed protein - octenyl succinic anhydride starch sodium composite solution at 20 - 25 °C at a speed of 600 rpm for more than 10 h, add cinnamon essential oil with the same solute weight to the obtained mixed solution and shear at high speed (9000 rpm) for 5 minutes to obtain a perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil composite solution;

[0105] (3) Homogenization treatment: Homogenize the perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil prepared in step (2) to form an emulsion; the high-pressure homogenization pressure is 35 MPa and the cycle is 4 times;

[0106] (4) Freeze-dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; the freeze-drying temperature is -40 °C and the freeze-drying time is 14 h;

[0107] (5) Pour 25 grams of sugar, 4 grams of salt, 2 grams of monosodium glutamate, 1 gram of pepper, 7 - 8 grams of soy sauce, 25 grams of rice vinegar, 10 grams of yellow rice wine, and 15 grams of water starch into a bowl and stir well;

[0108] (6) Add 2 grams of salt, 2 grams of monosodium glutamate, scallions - ginger - wine solution to the shredded meat, add an appropriate amount of dry corn starch and stir well, then add an appropriate amount of cooking oil and stir well;

[0109] (7) Pour oil into the pot. When the oil temperature reaches 60% heat, put in the shredded meat and stir - fry until it is dispersed. Then pour out the excess oil, add minced ginger and garlic and stir - fry evenly. Put in the agaric, shredded winter bamboo shoots, and shredded carrots and stir - fry evenly. Pour in the sauce and stir - fry evenly. Finally, put in the chopped scallions, bright oil, and 0.3% of the total mass of the dish of cinnamon essential oil microcapsules and stir - fry evenly, then it can be taken out of the pot and placed on a plate.

[0110] (8) Put the pre - prepared fish - flavored shredded pork with cinnamon essential oil microcapsules into a vacuum cooking bag and use a vacuum packaging machine for packaging.

[0111] (9) After taking out of the pot, put the packaged pre - prepared fish - flavored shredded pork into a high - voltage electrostatic field and treat it with a high - voltage electrostatic field of 30 kV intensity for 30 minutes.

[0112] Example 3

[0113] A preparation method of a marinated beef pre - prepared dish combined with cinnamon essential oil microcapsules and high - voltage electrostatic field is as follows:

[0114] (1) Prepare a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium: Disperse perilla seed protein and octenyl succinic anhydride starch sodium into ultrapure water respectively and stir for 12 h until completely dissolved to obtain octenyl succinic anhydride starch sodium solution and perilla seed protein solution respectively, where the mass concentration of both perilla seed protein and octenyl succinic anhydride starch sodium is 1%; Under stirring conditions, add 1 part of octenyl succinic anhydride starch sodium solution to 6 parts of perilla seed protein solution to obtain a mixed solution of perilla seed protein - octenyl succinic anhydride starch sodium;

[0115] (2) Prepare a perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil composite solution: Continuously stir the perilla seed protein - octenyl succinic anhydride starch sodium composite solution at 20 - 25 °C at a speed of 600 rpm for 10 h, add cinnamon essential oil with the same solute weight as the obtained mixed solution and shear at a high speed (9000 rpm) for 5 minutes to obtain a perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil composite solution;

[0116] (3) Homogenization treatment: Homogenize the perilla seed protein - octenyl succinic anhydride starch sodium - cinnamon essential oil prepared in step (2) under high pressure to form an emulsion; The high - pressure homogenization pressure is 35 MPa and circulates 4 times;

[0117] (4) Freeze-dry the emulsion formed in step (3) to form cinnamon essential oil microcapsules; the freeze-drying temperature is -40 °C and the freeze-drying time is 14 h;

[0118] (5) After cleaning the beef, cut it into large pieces, avoiding being too small. Put the beef into a pot, add enough cold water, heat it with high heat, skim off the floating foam after boiling, cook for 10 minutes, and then take out the beef and drain it for later use.

[0119] (6) Take a large pot, add an appropriate amount of water, and put the beef pieces into the pot. Add ginger slices, scallions, star anises, cinnamon twigs, and cooking wine. Then add light soy sauce, dark soy sauce, and white sugar to adjust the taste.

[0120] (7) Stew the beef over medium-low heat for about 2 hours until the beef becomes tender and flavorful. During this period, add an appropriate amount of water in a timely manner to keep the water level in the pot and submerge the beef.

[0121] (8) During the stewing process, add an appropriate amount of salt according to taste to adjust the saltiness. (9) When the beef is stewed until it is tender and flavorful, turn the heat to low and continue stewing until the soup thickens slightly. Take out the beef, slice it, and add 0.3% of the total mass of cinnamon essential oil microcapsules and stir well.

[0122] (10) Put the prepared dish of spiced beef combined with cinnamon essential oil microcapsules into a vacuum cooking bag and package it using a vacuum packaging machine.

[0123] (11) After taking out of the pot, put the packaged prepared dish of spiced beef into a high-voltage electrostatic field and treat it with a high-voltage electrostatic field of 30 kV intensity for 30 minutes.

[0124] It is the same as the production method of the prepared dishes in Comparative Examples 1-3, but in the last step of Examples 1-3, after adding 0.3% of the total mass of cinnamon essential oil microcapsules to the dish and stir-frying evenly and then taking out of the pot, it is further treated with a high-voltage electrostatic field of 30 kV intensity for 30 minutes. Figure 3 Compared with the changes in the total number of colonies and pH shown in Comparative Examples 3-4, the application of the high-voltage electrostatic field also further extends the shelf life of the prepared dishes. This shows that using perilla seed protein-octenyl succinic anhydride starch sodium as the wall material to encapsulate cinnamon essential oil can well maintain the antibacterial activity of cinnamon essential oil. Combining the application of the high-voltage electrostatic field in the prepared dishes can well extend the shelf life of the prepared dishes.

Claims

1. A method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields, characterized in that: The following steps are involved: (1) Preparing a perilla protein isolate-sodium starch octenyl succinate mixed solution: dispersing the perilla protein isolate and the sodium starch octenyl succinate in ultrapure water, respectively, and stirring until completely dissolved to obtain a sodium starch octenyl succinate solution and a perilla protein isolate solution, respectively; adding the sodium starch octenyl succinate solution to the perilla protein isolate solution under stirring to obtain a perilla protein isolate-sodium starch octenyl succinate mixed solution; (2) preparing a composite solution of perilla protein isolate-sodium starch octenyl succinate-cinnamon essential oil: continuously stirring a mixed solution of perilla protein isolate-sodium starch octenyl succinate, adding cinnamon essential oil to the obtained mixed solution of perilla protein isolate-sodium starch octenyl succinate and shearing at high speed to obtain a composite solution of perilla protein isolate-sodium starch octenyl succinate-cinnamon essential oil; (3) homogenization: the composite solution of perilla protein isolate-sodium starch octenyl succinate-cinnamon essential oil obtained in step (2) is subjected to high pressure homogenization to form an emulsion; (4) freeze-drying the emulsion formed in step (3) to form cinnamon essential oil microcapsules; (5) adding the cinnamon essential oil microcapsules prepared in step (4) to the pre-prepared dish; (6) placing the prepared dish to which cinnamon essential oil is added in step (5) into a high voltage electrostatic field for further treatment.

2. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In the perilla protein isolate-sodium starch octenyl succinate mixed solution described in step (1), the perilla protein isolate and the sodium starch octenyl succinate are stirred in ultrapure water for 10 to 12 hours respectively.

3. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (1), the mass concentration of the perilla protein isolate solution and the sodium starch octenylsuccinate solution is 1 to 3%.

4. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In the perilla protein isolate-sodium starch octenyl succinate mixed solution described in step (1), the mass concentration ratio of perilla protein isolate to sodium starch octenyl succinate is 4:1 to 6:

1.

5. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (2), the temperature of continuous stirring of the composite solution of perilla protein isolate-sodium starch octenyl succinate is 20-25° C., the rotation speed is 600-1000 rpm, and the time is 10-12 h; the composite solution of perilla protein isolate-sodium starch octenyl succinate-cinnamon essential oil is sheared at 8000-10000 rpm by a high-speed shearing machine for 4-8 minutes.

6. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (2), the added mass of cinnamon essential oil is 0.8 to 1.2 times the mass of the perilla protein isolate-sodium starch octenylsuccinate complex.

7. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (3), the high-pressure homogenization pressure of the composite solution of perilla protein isolate-sodium starch octenylsuccinate-cinnamon essential oil is 30-40 MPa, and the number of cycles is 2-4 times.

8. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (4), the freeze-drying temperature is -40 to -50°C, and the freeze-drying time is 13 to 15 hours.

9. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (5), the amount of cinnamon essential oil microcapsules added is 0.2-0.4% of the total mass of the prepared dish.

10. The method for extending the shelf life of pre-prepared dishes by combining cinnamon essential oil microcapsules and high-voltage electrostatic fields according to claim 1, characterized in that: In step (6), the voltage intensity of the high-voltage electrostatic field is 30 to 40 kV, and the treatment time is 25 to 35 minutes.

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